Chemopreventive Doses of Curcumin Protect Cells from Cadmium Induced Oxidative Stress

Circumstantial evidence link the high levels of environmental pollutants to increasedincidence of different chronic-degenerative diseases. Among these, the levels of heavy metals (HM)can certainly play a key role. On the other hand, a qualified literature highlights how differentphytochemicals, normally present in the diet are able to interfere with HM metabolism helping toreduce tissue concentrations and their negative effects on health. Curcumin (Cur) appears ofparticular interest for its protective properties against cadmium (Cd) toxicity. HL-60 cells,differentiated in human monocyte/macrophage lineage by vitamin D analogue EB1089, were preincubatedwith low doses of Cur (1 ?M) and treated for 24 h with 15 ?M Cd. Cell viability wasmeasured using CyQuant fluorescent dye. ROS (reactive oxygen species) and reduced glutathione(GSH) variations were assayed respectively by dichlorofluorescein-diacetate method andmonochlorobimane probe. The bioavailability of Cur in HL-60 cells was successfully performedusing RP-HPLC coupled with UV-Vis, MS/MS or MS/MSn. In differentiated HL-60 cells, the preincubationwith 1 ?M Cur determined a significant 20% protection towards the cytotoxicity inducedby Cd. The investigation of the mechanism of action evidenced that curcumin lowered ROS increasecaused by Cd by increasing GSH intracellular levels. The antioxidant activity of Cur wasstrengthened by the detection of free curcumin inside the cells after 5 min of treatment.